function Polyline(){
	this._these=new These();
	this._color=new Text().value("#ff0000");
	this._width=new Amount().value(1);
	this.point=function(n1,n2){
		if(n1 instanceof XY){
			var xy=new XY();
			xy.x().bind(n1.x());
			xy.y().bind(n1.y());
			this._these.child(xy);
			}
		else{this._these.child(new XY().x(n1).y(n2));}
		return this;
		};
	this.color=function(it){if(it==undefined)return this._color;
							if(it instanceof Text){this._color.bind(it);return this;}
							this._color.value(it);return this;};
	this.width=function(it){if(it==undefined)return this._width;
							if(it instanceof Amount){this._width.bind(it);return this;}
							this._width.value(it);return this;};
	this.render=function(context){
		context.beginPath();
		context.moveTo(this._these.find(0).x().value(),this._these.find(0).y().value());
		for(var i=1;i<this._these.size();i++){
			context.lineTo(this._these.find(i).x().value(),this._these.find(i).y().value());
			}
		context.lineCap="round";
		context.lineJoin="round";
		context.strokeStyle=this._color.value();		
		context.lineWidth=this._width.value();
		context.stroke();
		};
	}	
Polyline.prototype=new Layer();	